1. Field of the Invention
The present invention relates to work vehicles, and, more particularly, to a tendency of a work vehicle to tip which has an extended attachment.
2. Description of the Related Art
Work vehicles can generally be thought of as vehicles which are primarily equipped to do functional work. Such work vehicles can typically be found in the agricultural, construction, industrial and forestry technology sectors. For example, an agricultural harvester is used to harvest grain, a backhoe or excavator (also known as a track hoe) are used to dig and move dirt, a front end loader is used to pick up and move various types of material, depending on the type of attachment at the front end, a swather is used to cut and windrow crop, a crane is used to pick up and move heavy loads, and a feller/buncher is used to cut down, cut to length, stack and move trees. There are also many other types of work vehicles in these technology sectors.
For many types of work vehicles, and attachment assembly is pivotally connected to the frame or chassis of the vehicle and used to perform a work task during operation. For example, an excavator includes an upper frame which is pivotally mounted to a lower frame at a generally vertical pivot axis. The lower frame includes a pair of ground engaging tracks which provide motive force to the excavator. The upper frame includes among other things a power plant, transmission and an operator cab. An attachment assembly includes an inboard boom arm which is pivotally connected to the upper frame and an outboard boom arm which is pivotally connected to the distal end of the inboard boom arm. A material bucket positioned at the distal end of the outboard boom arm is operable to dig and move material such as dirt. As another example, a front end loader includes a loader frame which is positioned at the front of the vehicle and pivotally connected to the frame of the vehicle. Such a front-end loader typically includes a pair of boom arms which are pivotally connected to the loader frame, which in turn is rigidly mounted to the chassis of the work vehicle.
Work vehicles including a pivotal attachment assembly, as described above, can be more susceptible to tipping over during operation, depending on the magnitude of the variable load at the end of the attachment assembly, the position of the attachment assembly relative to the frame of the vehicle, and the slope of the ground on which the work vehicle is operating. Work vehicles of conventional design rely on operator knowledge to prevent tipping over.
What is needed in the art is a work vehicle that is less susceptible to tipping over, regardless of the operating conditions associated with a pivotal attachment assembly.